This release includes some important bug fixes as well as some exciting new features. In particular, Jess7.1a3 optimizes the "test" CE as well as some uses of functions during pattern matching, resulting in both memory and performance improvements. Jess 7.1a3 also introduces a new "dotted variable" notation for referring to facts and their slots; this new notation leads to both clearer syntax for humans, and easier code generation for rule processing tools.
We're recommending that everyone use this version for their development work. It's highly compatible with Jess 7.0, passes all the Jess 7.0 regression tests, and fixes some significant bugs from that earlier release.